“I feel like I just wandered into the soccer-themed bar mitzvah I never had,” said Roger Bennett, one-half of the Men in Blazers duo, seconds after bounding up onto the stage Friday evening to open the festivities at the first BlazerCon, a Comic-Con for soccer nerds.

Assembled before him at the Brooklyn Expo Center were hundreds of people — mostly 30-somethings, many of them men wearing the unofficial Men in Blazers uniform: a blazer, sneakers and a scarf bearing the colors of a favorite European soccer club. In the hall outside were Xbox stations loaded with the FIFA 2016 video game, a Topps booth with free packs of soccer trading cards, and more than a half-dozen wall-mounted flat-screen TVs that would soon broadcast the United States’ opening qualifying match for the 2018 World Cup.

Like its eponym and inspiration, BlazerCon was equal parts academic conference and cultural happening, a place for soccer fans to mingle, eat savory pies, drink Guinness and celebrate their shared object of devotion. But it was also a kind of informal trade show for international leagues and club executives to pitch themselves to the sport’s growing American fan base.

The procession of global soccer heavyweights who descended on the Brooklyn neighborhood of Greenpoint over the course of the next 24 hours served as a testament not only to how far the global game has come in the United States, but also to how much further its biggest brands believe it may yet go. England’s Premier League and Germany’s Bundesliga sent their chief executives. Roma sent its president. Everton sent its manager.

“You can look at China with that huge population, or India with that huge population,” Richard Scudamore, the executive chairman of the Premier League, said shortly before appearing in BlazerCon’s opening panel. “But China isn’t into sport the way the United States is, and India has cricket.”

Since Bennett and his partner Michael Davies created the Men in Blazers podcast in 2010, they have jokingly referred to soccer as “the sport of the American future — since 1972.” The future, at least as far as the sports business potential is concerned, may finally have arrived. More than 26 million people watched the United States win the Women’s World Cup final last summer. But more telling may be the steadily growing television audience for top European soccer: Last year’s Champions League final was watched by 2.2 million people in the U.S., and England’s Premier League is averaging about 550,000 viewers per game — an increase of about 150 percent since the 2012-13 season. In August, NBC Sports made a billion-dollar bet on the Premier League, extending its deal with the league for another six seasons for a rights fee that was double what it had been paying.

The Premier League may be America’s favorite soccer league, but it is just one of many that American fans are watching, to say nothing of the soccer videos and Vines from around the world that fill their social media feeds. (Much as the rise of radio helped spread interest in baseball and television turned football into a national obsession, the Internet has brought Lionel Messi and countless other international stars to U.S. tablets and smartphones.) The game’s growing popularity here is producing something of a gold rush among the top leagues and clubs overseas. Sports fandom tends to be generational — you root for your mom or dad’s team — or geographic. But a budding global soccer fan in the United States can choose to support whatever team from whatever country he or she chooses.

Bennett and Davies have played a small but not entirely insignificant role in soccer’s rise in the United States. In addition to their Men in Blazers podcast, they now produce a weekly soccer roundup for NBC Sports, occasional live shows and short documentary-style films. Between their love of “football” — both are British expatriates — their idiosyncrasies and their self-effacing humor (they refer to their commentary as “suboptimal ramblings”), they have developed a sizable fan base. As such, they provide direct access to an engaged niche audience, whimsical ambassadors to a demographic that a lot of soccer executives both here and abroad are trying very hard to reach.

There was a plain logic to hosting the inaugural BlazerCon in Brooklyn; the creative class were early and enthusiastic adopters of the European game. Walking to the conference in Greenpoint on Friday evening, it was hard to tell which bearded men in blazers were heading to BlazerCon and which ones were simply meeting up with friends at a nearby bar. The 1,300 tickets, priced at $225 (general admission) to $425 (VIP treatment), sold out quickly. GFOPs, or “Great Friends of the Pod,” as Men in Blazers fans are known, came in from all over the country for the event. If it was a branding opportunity for leagues and clubs, it was also one for Men in Blazers; at a booth run by Thomas Pink, you could get a Men in Blazers or BlazerCon patch sewn onto your blazer for free. For that matter, you could buy a (locally manufactured) blazer at another booth run by the Lower East Side clothier that Bennett and Davies frequent.

In the race to win over American fans, the Premier League — helped by a rich history and a common language — has started with a large and quite possibly insurmountable lead. But others are trying. French and Spanish teams routinely fill stadiums here on profitable summer tours. Last summer, the Bundesliga moved from little-known Gol TV to the much more widely distributed Fox Sports; a year earlier, its top club, Bayern Munich, opened an office in New York to better market itself to North American fans.

“For too long, the Bundesliga and most of the clubs were too conservative when it came to going outside the country,” Christian Seifert, the league’s chief executive, told me at BlazerCon. He ticked off a few of the Bundesliga’s main selling points, noting among other things that its games are the highest scoring among Europe’s major leagues.

The bigger English clubs like Manchester United, Liverpool and Arsenal are well-established in the United States, but now even some of their smaller, pluckier rivals are trying to make inroads here. One of them, AFC Bournemouth, was promoted to the Premier League this season for the first time in the club’s history, which dates to 1890. “Ironically, I think our rags-to-riches story resonates more with Americans than Brits,” said Bournemouth’s chairman, Jeff Mostyn.

Mostyn’s BlazerCon panel was titled “Achieving the Impossible,” but the very presence of such a modest European club in Brooklyn raised an important question: What does the future hold for America’s own professional soccer league, Major League Soccer? Will it be lifted by soccer’s rising tide, or buried by these new global challengers?

The league’s commissioner, Don Garber, was not given the most desirable time slot to make his pitch: 9 a.m. on Saturday, the morning after a lot of GFOPs had drunk a lot of pints of Guinness. But later in the day, a panel featuring three MLS owners moderated by former star Alexi Lalas drew a large crowd. MLS will finish its 20th season in the next few weeks, an impressive feat given its financially precarious start. Lalas asked the panelists to imagine what American soccer — and MLS in particular — would look like in another two decades. Joe Roth, the majority owner of the Seattle Sounders, predicted that soccer would be the second-most-popular sport in the United States, behind only footall. And that MLS would be one of the top five leagues in the world.

It is an ambitious vision, given the league’s strict salary cap, its modest TV revenue stream and viewership numbers that routinely lag far behind games beamed in from abroad. We can assess its accuracy at BlazerCon 2035.